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bioRxiv · 10.1101/2023.06.09.544165

IRF2BP2 counteracts the ATF7/JDP2 AP-1 heterodimer to prevent inflammatory overactivation in acute myeloid leukemia (AML) cells

Abstract

Acute myeloid leukemia (AML) is a hematological malignancy characterized by abnormal proliferation and accumulation of immature myeloid cells in the bone marrow. Inflammation plays a crucial role in AML progression, but excessive activation of cell-intrinsic inflammatory pathways can also trigger cell death. IRF2BP2 is a chromatin regulator implicated in AML pathogenesis, although its precise role in this disease is not fully understood. In this study, we demonstrate that IRF2BP2 interacts with the AP-1 heterodimer ATF7/JDP2, which is involved in activating inflammatory pathways in AML cells. We show that IRF2BP2 is recruited by the ATF7/JDP2 dimer to chromatin and counteracts its gene-activating function. Loss of IRF2BP2 leads to overactivation of inflammatory pathways, resulting in strongly reduced proliferation. Our research indicates that a precise equilibrium between activating and repressive transcriptional mechanisms creates a pro-oncogenic inflammatory environment in AML cells. The ATF7/JDP2-IRF2BP2 regulatory axis is likely a key regulator of this process and may therefore represent a promising therapeutic vulnerability for AML. Thus, our study provides new insights into the molecular mechanisms underlying AML pathogenesis and identifies a potential therapeutic target for AML treatment.

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BibTeXRIS

Fischer, S., Weber, L. M., Stielow, B., Frech, M., Simon, C., Koennecke, J., Forne, I., Nist, A., Bauer, U.-M., Stiewe, T., Neubauer, A., Liefke, R.. 2023-06-09. IRF2BP2 counteracts the ATF7/JDP2 AP-1 heterodimer to prevent inflammatory overactivation in acute myeloid leukemia (AML) cells. https://doi.org/10.1101/2023.06.09.544165

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